[verified] — Python 3 Deep Dive Part 4 Oop High Quality

class A: pass class B(A): pass class C(A): pass class D(B, C): pass

Sized.register(MyContainer) # Now MyContainer is considered a subclass of Sized python 3 deep dive part 4 oop high quality

This pattern gives validation, memory efficiency, and clean introspection — a practical blend of several deep OOP features. class A: pass class B(A): pass class C(A):

You don't use descriptors daily, but when you debug why @property works or build an ORM, you walk this path. 'y') def __init__(self

class Point: __slots__ = ('x', 'y') def __init__(self, x, y): self.x = x self.y = y

class Movable: def move(self): pass

print(MyClass.version) # 1.0